Of course perjury is impeachable. Or at least it was until the Clinton impeachment. Probably not anymore.
Either way you'd have to prove it was perjury. Assuming you're really getting at someone elected to office, of course.

What our government needs is an independent impeachment authority, which can refer bills of impeachment to the House that they are required to debate on the record.
Clearly the Congress is so befuddled by its War Powers that it cannot perform this duty with any reliability.